A known conventional translation assistance system for assisting translation of an original text into a target language comprises keyword extraction means that extracts a plurality of keywords from the original text to be translated and displays a list of the plurality of extracted keywords, data input means for inputting translation terms that correspond to the plurality of extracted keywords, batch replacement means that performs batch replacement of only the keywords in the original text with the input translation terms in the target language, and display means that displays the original text with only the keywords replaced with the translation terms in the target language (Patent Literature 1).
Known types of search for a translation term for a keyword include forward search, backward search, partial match search, and perfect match search, for example. There is also known a program product capable of displaying a translation term that corresponds to a particular word when the cursor of the mouse comes close to the particular word (for example, Roboword 2010 manufactured by Cross Language Inc.).